Centrifugal pumps which are specially designed to handle viscous fluids such as sludge, sewage, etc., are known. An example of such a pump is disclosed in my U.S. Pat. No. 3,499,388.
While my patented pump functions satisfactorily for its intended purpose, in that it is relatively easy to disassemble for cleaning, the pump is not as inexpensive to manufacture as desired. This is because the pump comprises cast parts which must be core-molded to provide the desired internal flow passages. Core-molded metal castings are complicated to produce, and hence they are expensive to manufacture. Accordingly, a centrifugal pump which does not require a core-molded casing is highly desirable.
So-called trash pumps handling entrained sand or other particles, such as sewage sludge, have certain parts which tend to wear due to the abrasive action of the material flowed through the pump. In addition, depending on the material being pumped, clogging of the internal pump passages can be a serious maintenance problem necessitating periodic cleaning with concomitant pump downtime. Thus, there is a demand for a trash pump which can be cleaned readily and/or disassembled to afford parts replacement.